Answer:
21
Step-by-step explanation:
(9x2 + 6x – 7) + (-9x - 5) = 21
Question 1:
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Total points = 100
Total question = 40
Type of questions : 2-points question and 4-points questions
Assumed all 40 questions are 2-points questions.
Total points = 40 x 2 = 80
Difference in points = 100 - 80 = 20 points
Difference in the 2 type of questions = 4 - 2 = 2
Number of 4 marks questions = 20 ÷ 2 = 10
Number of 2 marks questions = 40 - 10 = 30
Answer: There are 10 4-marks questions and 30 2-marks questions.
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Question 2:
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Let x be the number of offices you need to clean.
Total cost = 315 + 4x
Total revenue = 25x
To break even,
315 + 4x = 25x
21x = 315
x = 15
Answer: You need to clean 15 offices to break even.
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Question 3:
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Total distance (including return trip) = 255 + 255 = 510 miles
Total time taken = 1.7 + 1.5 = 3.2 hours
Speed = Distance ÷ time
Speed = 510 ÷ 3.2 = 159.38 miles/hour
Answer: The average speed is 159.38 miles/hour
If it’s 5% then it’s 0.05
x = 2
step 1 :
(2 • (5x + 2) • 2) - 48 = 0
step 2 :
4 • (5x + 2) - 48 = 0
Pulling out like terms :
20x - 40 = 20 • (x - 2)
step 4 :
20 • (x - 2) = 0
Equations which are never true :
Solve : 20 = 0
A a non-zero constant never equals zero.
Solving a Single Variable Equation :
Solve : x-2 = 0
Add 2 to both sides of the equation :
x = 2
Answer: 0.05508474576
Step-by-step explanation: